Asked by: Finn Bogdan, Switzerland
That depends on where you are. In a natural environment that’s rich in edible plants and animals, being good at maths, logic and written language is virtually useless. Instead, you need years of experience of hunting, choosing plants, building shelters and lighting fires. Above all, you need social skills not measured in IQ tests. If you can’t maintain friendships, make alliances, deal with disputes and keep track of liars, cheats and deeds of kindness then you won’t survive long.
In contrast, in a modern environment full of computers, electronic banking and online shopping, a high IQ is increasingly necessary. In societies with a welfare state, you’re unlikely to starve. But researchers in the field of ‘cognitive epidemiology’ find that people with lower IQs are less healthy and die younger. For example, a drop of 15 points in IQ translates to a 24 per cent increase in morbidity and a 20 per cent lower chance of living beyond age 75. So in the modern world IQ really does aid survival.
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